1. P16221 – FSAE Shock Dynamometer System Level Design Review September 29, 2015

2. Aung Toe – EE Jim Holmes – EE – Project Manager Sal Fava – ME – Chief Engineer Chris Batorski – ME – Facilitator Andrew Dodd – ISE P16221 – MSD Team

3. Background (5 min) System Analysis (10 min) Concept and Architecture Development (5 min) System Level Proposal (10 min) Engineering Analysis (15 min) Risk Assessment (5 min) Test Plan(how we will meet the specs) (5 min) Updated Project Plan (5 min) Question and Answer (15 min) Agenda

4. A shock dynamometer is a measurement device supply an input displacement vs time profile measure the response (both displacement and force) of a damper. Overall: a tool used by engineers to tune the suspension and ride quality of a vehicle in any application Background: What is a Shock Dynamometer?

5. The goal of this project – Design a device to characterize dampers – Capable of supplying a displacement input profile in time and measuring force, displacement, and temperature responses of a damper – Existing machines will be analyzed for compatibility. If there are no existing machines that will support the damper dyno integration, a new machine will be developed Background: Problem Statement

6. 1.Cost less than $3,000 2.Able to be moved in the shop easily 3.Reproduce damper displacements from track data 4.Measure damper forces 5.Measure damper shaft position 6.Measure damper temperature during test 7.Save and recall test data for post processing 8.Maximum footprint of 4’ x 4’ 9.Accommodate wide range of damper sizes Background: Customer Requirements

7. Background: Engineering Requirements

8. Predicted Costs

10. House of Quality Overall Picture 1 2 3 4 5

11. House of Quality 1. Customer Reqs

12. House of Quality 2. Functional Reqs

13. House of Quality 3. Inter-relationships

14. House of Quality 4. Roof

15. House of Quality 5. Targets

16. Functional Decomposition Damper Characterization Accessing Damper/Prep TestRunning Test Data Collection User Safety/Results Output

17. Functional Decomposition Accessing Damper/Test Prep

18. Functional Decomposition Running Test

19. Functional Decomposition Data Collection

20. Functional Decomposition User Safety/Result Output

21. System Level Design Concept Data Test Commands Post Processed Results

22. System Level Design Flowchart

23. Morph Chart

24. Morph Chart Cont.

26. Ball Screw Actuation Capable of track data input profile – >10 in/s shaft speed – >1500 lbf input force System Level Proposal

27. Cam/Rotary type motor sizing Memory Requirements Microprocessor Read Speed Testing Serial Speed Analysis Load Cell Analysis Engineering Analysis

28. Determine a power requirement – Inputs 10 in/s shaft speed 1500 lbf load capability – Output 2.72 Hp – Conclusion Need a 3-5 Hp motor Cam/Rotary motor

29. Calculate memory requirements for data acquisition – Inputs Track data sampled at 500 Hz (0.002 seconds between samples) Data consists of a pair of numbers (time, displacement) – Outputs 1,800,001 samples 13.74 MB requirement – Conclusion Eliminate time and send measurements at a constant 0.002 Record 1-5 minutes of data and send to PC in chunks Memory

30. Read Speed Test – Simulated series of analog input reads – ATmega328P-XMINI – Results Mean 339.3 us Min 332 us Max 432 us – Conclusion Should have plenty of time to control actuator at 125Hzcontrol speed 5 variables in sketch took 16% of available stack space Microprocessor

31. Serial Speed Analysis – Inputs Memory Requirements (64 bits of data in 0.002s) – Output 32,000 bits/s – Conclusion- feasible baud rates: 28400 57600 115200 RS-232

32. Source a load cell that meets required specifications – Inputs 1500 lbf @ 500 Hz No measurement phase lag (+) and (-) force measurement capabilities < $1000 – Output PCB 1403-14A/084A100 – Conclusion Exceeds all physical requirements Need a discount or sponsor (> $1000) Load Cell

33. Risk Assessment

34. Emergency circuit breakers – Open enclosure door, verify the system stopped – Press emergency switch, verify the system stopped Sensor measurements – Force (give a known weight – get the reading) – Temperature (measure room temperature) – Position (command to move to a known distance – measure) – Verify the measurements are within acceptable range Test Plan

35. Data collection speed (~250 Hz – 4ms period) – Collect data from the sensors and time taken Track frequency (~125 Hz – 8ms period) – Command the controller to move a period within 8 ms – Verify the frequency from sensor data Variable stroke range – Command the controller to vary the stroke range – Verify with the reading from linear potentiometer Data format – Verify.csv format in file system Test Plan

36. Replay track data – Use the data from.csv and produce graphs Sturdy base and mounting to withstand vibrations – Apply 100 lbs to top, measure deflection (<0.005in) Eye-to-eye distance/ overall footprint – Tape measurements Mobility – Customer judgement: 1 (zero mobility) – 10 (excellent mobility) Test Plan

37. Updated Project Plan

38. Questions?